Dry heat dental press



' March 27, 1934.

R. A. STEHLEY 1,952,951

DRY HEAT DENTAL PRESS Filed. May 19. 1931 3 Sheets-Sheet 1 gwoemtov March 27, 1934. R, A. STEHLEY DRY HEAT DENTAL PRESS Filed Mal 19, 1931 3 Sheets- Sheet 2 gmantoz March 27, 1934. R. A. STEHLEY DRY HEAT DENTAL PRESS Filed May 19, 1951 3 Sheets-Sheet 3 amnion Patented Mar. 27, 1934 UNITED STATES PATENT OFFICE DRY HEAT DENTAL PRESS Roszel A. Stehley, Philadelphia, Pa. Application May 19, 1931, Serial No. 538,561

1 Claim. (01. 18--17) This invention relates to a dry heat dental press and has for its primary object to provide, in a manner as hereinafter set forth, an article of such character by means of which live steam may be eliminated in pressing dentures.

A further object of the invention is to provide a press of the character aforesaid which is electrically and hydraulically operated.

A further object of the invention is to provide a press of the character aforesaid in which the operator may see the pressing procedure at all times, thereby enabling the finer details of the cast to be more thoroughly reproduced.

A further object of the invention is to provide a press of the character aforesaid by means of which the retention of the original density and color of the denture blank is assured.

A further object of the invention is to provide, in a manner as hereinafter set forth, a dry heat dental press, so constructed that when operated a flask carrying a denture blank will be subjected to uniform pressure and uniformly heated for materially reducing the possibility of injury to the denture blank.

A further object of the invention is to provide,

, in a manner as hereinafter set forth, a dryheat dental press so constructed that the heat will be confined and directed to the flask, resulting in the minimum Waste and dissipation of the heat.

A further object of the invention is to provide, in a manner as hereinafter set forth, a dry heat dental press including as a part thereof a heat transmitting or distributing means so formed and arranged to provide for a saving in material and .35 area to heat, for elimination of unnecessary waste of heat, for confining the heat within the press and for reducing to a minimum the radiation of the heat from the press.

With the foregoing and other objects in view,

340 the invention consists of the novel construction,

combination and arrangement of parts as hereinafter more particularly described, and as illustrated in the accompanying drawings wherein is shown an embodiment of the invention, but it is to be understood that the description and drawings are to be considered as illustrative rather than limitative.

In the accompanying drawings in which like numerals are employed to designate like parts throughout the several views:

Figure 1 is an elevation of a press in accordance with this invention.

Figure 2 is a top plan thereof.

.55. Figure 3 is an enlarged fragmentary section taken substantially on the line indicated at 33 I in Figure 2.

Figure 4 is an'enlarged section taken on the line 4-4 of Figure 3.

Figure 5 is a sectional plan taken on the line 69 55 of Figure 1.

Figure 6 is a sectional plan taken on the line 66 of Figure 1.

Fig. '7 is a plan of one of the heating devices forming a part of the press.

Referring to the drawings in detail, the numeral 1 indicates a base which supports a plurality of upright posts 2 having a stationary cross head or platen 3 secured to the upper ends thereof.

Slidably mounted between the posts 2 is a movable cross head or platen 4 which is adapted to be moved toward and from the cross head 3 by means of a hydraulic jack 5 mounted on the base 1. Carried by the movable cross head 4 is a heating device indicated generally at 6 and including a heat transmitting or distributing plate 7 seating against the upper face of the cross head. Se-

cured to the'plate '7 are a pair of base plates 8 which are disposed within recesses 9 formed in the upper face of the cross head 4. The plates 8 are separated from the walls of the recesses 9 at the sides of the latter by means of insulating members 10, and at the bottoms of the recesses by means of heat insulating members 11. Disposed between the plates 8 and the plate '7 are a pair of substantially U-shaped insulating members 12 arranged in spaced relation and having interposed therebetween a heating element 13 having a pair of terminals 14 connected with a suitable electrical lead in line 15. The terminals 14 are insulated from the plates 8 and cross head 4 by means of an insulating member 16. The plates 8 and insulating members 12 are connected to the plate 7 by means of suitable screws 17. The terminals 14 extend through the cross head 4 and have their projecting ends concealed within a housing 18 secured to the cross head 4 by means of a suitable bolt 19.

Carried by the stationary cross head 3 is a heating device indicated generally at 20 which is the same in every respect as the heating device 6 and will not be specifically described. The heating element of the heating device 20 includes a pair of terminals 21 which are connected by means of a conductor 22 with the terminals 14. The terminals 21 extend through the cross head 3 and have their projecting ends concealed within a housing 23 secured to the cross head 3 by means of a suitable bolt 24.

In the use of a dental press in accordance with this invention, a denture blank contained in a flask such as 25 is seated on the heating device 6 and the cross head 4 is moved to a position with respect tothe cross head 3 to bring the flask 25 into contact with the heating device 20. With the parts in this position, the current is turned on until the heating devices 6 and 20 are thoroughly heated, afterwhich the jack 5 is placed" in operation whereby pressure and heat are applied simultaneously to the flask until the.

latter is almost closed. When the flask is nearly closed, the current may be turned off, as the heat already generated will be sufiicient to complete the pressing procedure. The heat of the press is indicated at all times by means of a heat indicator 26 mounted on the cross head 3 and projecting into an opening 2'7 extending therethrough.

The construction of the press is such that it includes those factors which are of the utmost importance during its operation upon a flask carrying a denture blank. These factors provide for an even pressure on the flask and the even or uniform heating of the latter. It is desirable that the heat which is to be applied to the flask should be applied from spaced sections of a heating element through the medium of a heat transmitting or distributing plate in such a manner that the greatest amount of heat should not be applied to the center of the flask, but to the sides 01. the flask so that it will radiate to the center. The particular form of heating element in connection with the particular form of heat transmitting or distributing plate and the specific manner in which they are assembled all as referred to, will obtain the application of heat to the flask in the manner desired.

As the heat transmitting or distributing plate is of less area than that face of the cross head to which it is attached and of greater area than the recess, this results in a saving of material, creates a less area to heat, eliminates unnecessary waste of heat, causes a reduction in Weight carried by the cross head and confines the heat within the area of the cross head, materially reducing the heat radiating from the press.

The manner of setting up of the heating element with respect to the base plate, and the manner of setting up said element and base with respect to the bottom and side Walls of the recess provide for directing the heat generated, outwardly to the heat transmitting or distributing plate, and prevents the heat from being dissipated through a cross head, whereby the heating step is facilitated and a saving in heat is had.

It is thought that the many advantages of an electric hydraulic dry heat dental press in accordance with this invention will be readily ap-- parent, and although the preferred embodiment of the invention is as illustrated and described, it is to be understood that changes in the size, shape and arrangement of parts may be restorted to, so long as such changes fall Within the scope of the invention as defined in the appended claim.

What I claim is:

In a dry heat dental press, a pair of parallel cross heads, one being stationary and the other being movable towards and from the stationary cross head, one of said cross heads having that face opposing the other cross head provided with a U-shaped recess spaced from the edges of said face, a base plate mounted in each side of the recess and heat insulated from the bottom and walls of such side, a heat transmitting plate of less area than said face and of greater area than said recess and being anchored against said face for closing said recess, an electrical heating element mounted in the recess and formed of a pair of sidewise opposed parallel spaced sections electrically connected together at one end at the base of the recess, each section of said element positioned in one side of the recess against a base plate and electrically insulated from the heat transmitting plate, means for anchoring the heat transmitting plate, said sections and base plates together, and a pair of binding posts extending into the recessed cross head and electrically connectedrto the other ends of said sections, said posts extending through the base plates and insulated from the latter and the recessed cross head. 1 i 5 NE -E m! ROSZEL A. STEHLEY. 

